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.TH SETSOCKOPT 3XNET "Jan 21, 2007"
.SH NAME
setsockopt \- set the socket options
.SH SYNOPSIS
.LP
.nf
\fBcc\fR [ \fIflag\fR... ] \fIfile\fR... \fB-lxnet\fR [ \fIlibrary\fR... ]
#include <sys/socket.h>

\fBint\fR \fBsetsockopt\fR(\fBint\fR \fIsocket\fR, \fBint\fR \fIlevel\fR, \fBint\fR \fIoption_name\fR,
     \fBconst void*\fR\fIoption_value\fR, \fBsocklen_t\fR \fIoption_len\fR);
.fi

.SH DESCRIPTION
.sp
.LP
The \fBsetsockopt()\fR function sets the option specified by the
\fIoption_name\fR argument, at the protocol level specified by the \fIlevel\fR
argument, to the value pointed to by the \fIoption_value\fR argument for the
socket associated with the file descriptor specified by the \fIsocket\fR
argument.
.sp
.LP
The \fIlevel\fR argument specifies the protocol level at which the option
resides.  To set options at the socket level, specify the \fIlevel\fR argument
as \fBSOL_SOCKET\fR.  To set options at other levels, supply the appropriate
protocol number for the protocol controlling the option.  For example, to
indicate that an option will be interpreted by the TCP (Transport Control
Protocol), set \fIlevel\fR to the protocol number of TCP, as defined in
the<\fBnetinet/in.h\fR> header, or as determined by using
\fBgetprotobyname\fR(3XNET).
.sp
.LP
The \fIoption_name\fR argument specifies a single option to set.  The
\fIoption_name\fR argument and any specified options are passed uninterpreted
to the appropriate protocol module for interpretations. The
<\fBsys/socket.h\fR> header defines the socket level options. The options are
as follow
.sp
.ne 2
.na
\fB\fBSO_DEBUG\fR\fR
.ad
.RS 17n
Turns on recording of debugging information.  This option enables or disables
debugging in the underlying protocol modules.  This option takes an \fBint\fR
value. This is a boolean option.
.RE

.sp
.ne 2
.na
\fB\fBSO_BROADCAST\fR\fR
.ad
.RS 17n
Permits sending of broadcast messages, if this is supported by the protocol.
This option takes an \fBint\fR value. This is a boolean option.
.RE

.sp
.ne 2
.na
\fB\fBSO_REUSEADDR\fR\fR
.ad
.RS 17n
Specifies that the rules used in validating addresses supplied to
\fBbind\fR(3XNET) should allow reuse of local addresses, if this is supported
by the protocol. This option takes an \fBint\fR value. This is a boolean
option.
.RE

.sp
.ne 2
.na
\fB\fBSO_KEEPALIVE\fR\fR
.ad
.RS 17n
Keeps connections active by enabling the periodic transmission of messages, if
this is supported by the protocol.  This option takes an \fBint\fR value.
.sp
If the connected socket fails to respond to these messages, the connection is
broken and threads writing to that socket are notified with a \fBSIGPIPE\fR
signal.
.sp
This is a boolean option.
.RE

.sp
.ne 2
.na
\fB\fBSO_LINGER\fR\fR
.ad
.RS 17n
Lingers on a \fBclose\fR(2) if data is present.  This option controls the
action taken when unsent messages queue on a socket and \fBclose\fR(2) is
performed.  If \fBSO_LINGER\fR is set, the system blocks the process during
\fBclose\fR(2) until it can transmit the data or until the time expires.  If
\fBSO_LINGER\fR is not specified, and \fBclose\fR(2) is issued, the system
handles the call in a way that allows the process to continue as quickly as
possible.  This option takes a \fBlinger\fR structure, as defined in the
<\fBsys/socket.h\fR> header, to specify the state of the option and linger
interval.
.RE

.sp
.ne 2
.na
\fB\fBSO_OOBINLINE\fR\fR
.ad
.RS 17n
Leaves received out-of-band data (data marked urgent) in line. This option
takes an \fBint\fR value. This is a boolean option.
.RE

.sp
.ne 2
.na
\fB\fBSO_SNDBUF\fR\fR
.ad
.RS 17n
Sets send buffer size.  This option takes an \fBint\fR value.
.RE

.sp
.ne 2
.na
\fB\fBSO_RCVBUF\fR\fR
.ad
.RS 17n
Sets receive buffer size. This option takes an \fBint\fR value.
.RE

.sp
.ne 2
.na
\fB\fBSO_DONTROUTE\fR\fR
.ad
.RS 17n
Requests that outgoing messages bypass the standard routing facilities. The
destination must be on a directly-connected network, and messages are directed
to the appropriate network interface according to the destination address. The
effect, if any, of this option depends on what protocol is in use. This option
takes an \fBint\fR value. This is a boolean option.
.RE

.sp
.ne 2
.na
\fB\fBSO_MAC_EXEMPT\fR\fR
.ad
.RS 17n
Sets the mandatory access control on the socket. A socket that has this option
enabled can communicate with an unlabeled peer if the socket is in the global
zone or has a label that dominates the default label of the peer. Otherwise,
the socket must have a label that is equal to the default label of the
unlabeled peer. \fBSO_MAC_EXEMPT\fR is a boolean option that is available only
when the system is configured with Trusted Extensions.
.RE

.sp
.ne 2
.na
\fB\fBSO_ALLZONES\fR\fR
.ad
.RS 17n
Bypasses zone boundaries (privileged). This option stores an \fBint\fR value.
This is a boolean option.
.sp
The \fBSO_ALLZONES\fR option can be used to bypass zone boundaries between
shared-IP zones. Normally, the system prevents a socket from being bound to an
address that is not assigned to the current zone. It also prevents a socket
that is bound to a wildcard address from receiving traffic for other zones.
However, some daemons which run in the global zone might need to send and
receive traffic using addresses that belong to other shared-IP zones. If set
before a socket is bound, \fBSO_ALLZONES\fR causes the socket to ignore zone
boundaries between shared-IP zones and permits the socket to be bound to any
address assigned to the shared-IP zones. If the socket is bound to a wildcard
address, it receives traffic intended for all shared-IP zones and behaves as if
an equivalent socket were bound in each active shared-IP zone. Applications
that use the \fBSO_ALLZONES\fR option to initiate connections or send datagram
traffic should specify the source address for outbound traffic by binding to a
specific address. There is no effect from setting this option in an
exclusive-IP zone. Setting this option requires the \fBsys_net_config\fR
privilege. See \fBzones\fR(7).
.RE

.sp
.LP
For boolean options, \fB0\fR indicates that the option is disabled and \fB1\fR
indicates that the option is enabled.
.sp
.LP
Options at other protocol levels vary in format and name.
.SH USAGE
.sp
.LP
The \fBsetsockopt()\fR function provides an application program with the means
to control socket behavior.  An application program can use \fBsetsockopt()\fR
to allocate buffer space, control timeouts, or permit socket data broadcasts.
The <\fBsys/socket.h\fR> header defines the socket-level options available to
\fBsetsockopt()\fR.
.sp
.LP
Options may exist at multiple protocol levels. The \fBSO_\fR options are always
present at the uppermost socket level.
.SH RETURN VALUES
.sp
.LP
Upon successful completion, \fBsetsockopt()\fR returns \fB0\fR. Otherwise,
\fB-1\fR is returned and \fBerrno\fR is set to indicate the error.
.SH ERRORS
.sp
.LP
The \fBsetsockopt()\fR function will fail if:
.sp
.ne 2
.na
\fB\fBEBADF\fR\fR
.ad
.RS 15n
The \fIsocket\fR argument is not a valid file descriptor.
.RE

.sp
.ne 2
.na
\fB\fBEDOM\fR\fR
.ad
.RS 15n
The send and receive timeout values are too big to fit into the timeout fields
in the socket structure.
.RE

.sp
.ne 2
.na
\fB\fBEFAULT\fR\fR
.ad
.RS 15n
The \fIoption_value\fR parameter can not be accessed or written.
.RE

.sp
.ne 2
.na
\fB\fBEINVAL\fR\fR
.ad
.RS 15n
The specified option is invalid at the specified socket level or the socket has
been shut down.
.RE

.sp
.ne 2
.na
\fB\fBEISCONN\fR\fR
.ad
.RS 15n
The socket is already connected, and a  specified option can not be set while
the socket is connected.
.RE

.sp
.ne 2
.na
\fB\fBENOPROTOOPT\fR\fR
.ad
.RS 15n
The option is not supported by the protocol.
.RE

.sp
.ne 2
.na
\fB\fBENOTSOCK\fR\fR
.ad
.RS 15n
The \fIsocket\fR argument does not refer to a socket.
.RE

.sp
.LP
The \fBsetsockopt()\fR function may fail if:
.sp
.ne 2
.na
\fB\fBENOMEM\fR\fR
.ad
.RS 11n
There was insufficient memory available for the operation to complete.
.RE

.sp
.ne 2
.na
\fB\fBENOBUFS\fR\fR
.ad
.RS 11n
Insufficient resources are available in the system to complete the call.
.RE

.sp
.ne 2
.na
\fB\fBENOSR\fR\fR
.ad
.RS 11n
There were insufficient STREAMS resources available for the operation to
complete.
.RE

.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(7) for descriptions of the following attributes:
.sp

.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
Interface Stability	Standard
_
MT-Level	MT-Safe
.TE

.SH SEE ALSO
.sp
.LP
.BR bind (3XNET),
.BR endprotoent (3XNET),
.BR getsockopt (3XNET),
.BR socket (3XNET),
.BR attributes (7),
.BR standards (7)
